Shield for tunneling in unstable grounds

ABSTRACT

A TUNNELING SHIELD COMPRISES A SKIN IN WHICH HORIZONTAL GIRDERS ARE RIGIDLY FIXED SUCH THAT THE GIRDERS DIVIDE THE SHIELD INTO DECKS. SLIDING PLATFORMS MOVABLE LONGITUDINALLY OF THE SKIN ARE PROVIDED FOR REDUCING THE GROUND RESISTANCE WHEN THE SHIELD IS FORCED THEREINTO AND FOR KEEPING THE GROUND TALUS FROM CRUMBLING. THE PLATFORMS ARE FORCED INTO THE GROUND SEPARATELY FROM THE SHIELD SKIN AND SUBSEQUENT TO EACH SHIELD CUT AND PIVOTAL SCRAPER CONVEYERS ARE MOUNTED ABOVE THE PLATFORM FOR REMOVAL OF EXCAVATED GROUND.

1971 v. P. SHMAKOV AL ma ma SHIELD FOR TUNNELING IN UNSTABLE GROUNDS 2Sheets-Sheet 1 Filed Aug. 9, 1968 Jan. 26, 1971 v, SHMAKOV ET AL 355fl2SHIELD FOR TUNNELING IN UNSTABLE GROUNDS Filed Aug. 9, 1968 2Sheets-Sheet 2 United States Patent 3,558,192 SHIELD FOR TUNNELING INUNSTABLE GROUNDS Vasily Pavlovich Shmakov, Ul. Marshala Birjuzova 26,kv. 22; Vitaly Alexeevich Eremin, Bagrationovsky proezd 2, kv. 48; SemenBorisovich Kvasha, Begovaya til. 38, kv. 36; Natalia GrigorievnaKaganovich, Ul. Myaskovskogo 16/8, kv. 17; Tatiana NikolaevnaDobrenyakina, Leninsky prospekt 25, kv. 52; Viktor NikolaevichVanjushiu, Ul. Udaltsova 10, kv. 168; Petr Vasilievich Sakharov,Starozykovsky proezd 4, kv. 51; Boris Pavlovich Voronov, NaberezhnayaMaxima Gorkogo 4/22, kv. 170; Vasily Dementievich Polezhaev,Leningradsky prospekt 62, kv. 122; Pavel Semenovich Smetankin, Ul.Chkalova 24/30, kv. 20; Evgeny Pavlovich Sobolev, Ul. Chernyakhovskogo6, kv. 41; Kazimir Stanislavovich Yanchevsky, Ul. Obraztsova 12, kv. 14;Mikhail Semenovich Grishin, Novokuznetskaya u]. 24, kv. 33; Pavelsemenovich Burtsev, Bolshoi Chudov per. 8-a, kv. 64; and PavelAlexeevich Chasovitin, Leningradsky prospekt 62, kv. 198, all of Moscow,U.S.S.R.

Filed Aug. 9, 1968,'Ser. No. 751,624 Int. Cl. E0lg 3/03 U.S. Cl. 299-334 Claims ABSTRACT OF THE DISCLOSURE A tunneling shield comprises a skinin which horizontal girders are rigidly fixed such that the girdersdivide the shield into decks. Sliding platforms movable longitudinallyof the skin are provided for reducing the ground resistance when theshield is forced thereinto and for keeping the ground talus fromcrumbling. The platforms are forced into the ground separately from theshield skin and subsequent to each shield cut and pivotal scraperconveyers are mounted above the platform for removal of excavatedground.

The present invention relates to a shield for tunneling in unstableground.

There are known shields for tunneling in unstable ground by forcing theshield skin into the ground. These shields are provided with rigidlyfixed transverse stiffening girders mounted in decks, thereby making itpossible to keep unstable (loose) ground at an angle of natural slope.

A disadvantageous feature of the known shields is that the transversegirders increase the head resistance when driving the shield into theground.

An object of the invention is to eliminate this disadvantage of theknown shields.

Other objects of the invention are to insure the shield operation oncurved portions of the route and at a local increase of the resistanceof ground to cutting, to keep the face in proper condition throughoutits whole width in compliance with the horizontal projection of theground talus in its natural state, and to facilitate the cleaning of thetunnel head face of large inclusions.

In the accomplishment of these and other objects of the invention, theshield for tunneling in unstable ground is provided with slidingplatforms mounted on transverse girders, said platforms being connectedwith power cylinders adapted for moving the platforms forward along theshield motion and for forcing them into the ground independently of theshield advance. The platforms keep the ground from crumbling and make itpossible to place the transverse girders with a lag relative to thecutting edge of the shield skin. This permits sharp reduction of theground resistance when forcing the shield thereinto.

In this case, it is more expedient that the power cylinders bepositioned in telescopic guides whose movable members are connected bymeans of vertical hinges to the front portions of the platforms, whilethe power cylinders are hinged at one of their ends to the movable partof the telescopic guides and, by their other ends, to the transversegirders. This makes it possible to place the sliding platforms at acertain angle to the face plane when cutting a curved portion of thetunnel and to protect the shield from damage when the face ground isnon-homogeneous.

To preserve the face unbroken throughout its whole width and to withdrawthe ground along the whole outline of the ground talus, the decks of theshield are provided with scraper conveyers each of the latter beingmounted for the possibility of making a complete turn in horizontalplane on a carriage travelling along the shield axis. This insures theexcavation of ground talus in compliance with its horizontal projectionas well as a free access to the face for cleaning it from possible largeinclusions.

Given hereinbelow is the detailed description of the invention withreference to the accompanying drawing, wherein:

FIG. 1 is a longitudinal section of the shield according to theinvention;

FIG. 2 is a view of the shield from the face thereof; and

FIG. 3 is a plan view of the top deck of the shield.

Fixed in the shield frame or skin 1 (FIGS. 1, 2 and 3) are transversegirders 2 bearing sliding platforms 3 provided in their front portionswith cutting edges. Each platform is connected by hinges 4 with movablemembers 5 of telescopic guides 6 fixed to the transverse girders 2.Hinged inside the movable members 5 of the guides 6 are rods 7 ofhydraulic cylinders 8. The hydraulic cylinders 8 are connected by hinges9 to the transverse girders 2.

The transverse girders 2 are provided with openings 10 for removal ofexcavated ground.

Mounted above the girders are scraper conveyers 11 positioned oncarriages 12 by means of hinges 17 to permit rotation of conveyers 11 inthe horizontal plane.

The carriages 12 can travel along guides 13 parallel to the longitudinalaxis of the shield and are connected with tie rods 14 and 14' adjustablein length. The free ends of the top deck tie rods 14 can be fixed to theguide 13, while the tie rods 14' of the next lower deck are coupled withthe platforms 3. The slewing mechanisms (not shown in the drawings) ofthe carriages 12 make it possible to set the conveyers 11 at any angleto the face as well as to set them in compliance with the outline of thebase of ground talus depending upon the physical and chemical propertiesof the ground in the face.

To direct excavated ground to the bottom of the shield, provision ismade for chutes 15 arranged under the openings 10 of the transversegirders 2. The bottom of the shield accommodates a device for loadingexcavated ground into cars (not shown in the drawings). The shieldhouses hydraulic jacks 16.

The shield operates as follows.

The shield skin 1, thrust against the tunnel lining by means of thehydraulic jack 16, is forced into the ground. In this case, the platform3 encountering the resistance of ground lag behind the cutting edges ofthe shield since there is no working pressure in the hydraulic cylinders8 at the moment. After the shield reaches the present value of advance,it is stopped, and the platform 3 are forced into the ground by thehydraulic cylinders 8. Since the platforms 3 can rotate in thehorizontal plane around 3 the hinges 4, the driving of tunnels on curvesof small radius becomes easier and the shield can be protected fromdamage when the geological structure of the face is non-homogeneous.

Since the ground, depending on its composition and Water saturation, mayhave different angles of natural slope, the excavation of the ground iscarried out in layers parallel to the surface of the ground talus. Theapex of the angle of the ground talus in each deck, in the course of theexcavation of ground must not get beyond the edge of the shield skin 1or the platform 3. To this end, the tie rods 14 of the top deck arefixed on the guides 13. By adjusting the length of the tie rods 14 and14 taking into account the angle of natural slope, the carriages 12 andshield skin 1 are mutually positioned in the top deck, and the carriages12 and platforms 3 in the next deck. The conveyors 11 are turned on thecarriages 12, then set according to the curve of ground talus, and thepower drive of the conveyers is switched The conveyers 11 of the topdeck deliver excavated ground to the opening of the upper transversegirder 2, wherefrom it arrives at the opening 10 of the lower girderand, along with ground excavated by the shield face scraper conveyers 11of the middle deck, the excavated ground flows through the chute 15towards the lower deck onto a loading device. As the ground isexcavated, the shield and then the platforms 3 are moved ahead. Theshield advances while the conveyers 11 operate, which considerablylowers the resistance of the ground. When there are large inclusions inthe face ground, e.g. boulders, the rods 14 or 14 are disconnected andthe conveyers 11 are rolled back along the guides 12, thereby providingfree access to the face for the removal of the boulders.

After cleaning the face, the conveyors 11 are set into the operatingposition, and the tie rods 14 or 14' are secured in place.

What is claimed is:

1. A shield for tunneling in unstable grounds comprising: a skin; jacksmounted in said skin for forcing said skin into a face in the ground insteps; transverse girders fixed in said skin and dividing the same atthe face into decks; sliding platforms positioned on said transversegirders for travel longitudinally of the direction of skin advance; andmeans connected with said sliding platforms to move the platformsforward in the direction of skin advance and to force the platforms intothe ground of the face, independently of the progress of the skin andsubsequent to each step of advance thereof.

2. A shield according to claim 1 wherein the means to move the platformsforward comprises hydraulic power cylinders connected to said platforms,telescopic guides coupled to and receiving said cylinders, said guidesincluding movable parts and vertically hinged joints connecting saidmovable parts with said platforms.

3. A shield according to claim 1 comprising face end scraper conveyorsabove each girder, a carriage for each conveyor displaceablelongitudinally of the skin, and means connecting each of the scraperconveyors to the associated carriage for rotation about a vertical axis.

4. A shield according to claim 3 wherein said girders are provided withopenings which are positioned with respect to the scraper conveyers fordownward transport of excavated ground fed to the openings by thescraper conveyers.

References Cited UNITED STATES PATENTS 3,372,553 3/1968 Samokov et a1.61-85 FOREIGN PATENTS 1,205,576 11/1965 Germany 299-33 1,222,527 8/1966Germany 299-33 6509,733 l/1966 Netherlands 61-85 ERNEST R. PURSER,Primary Examiner US. Cl. X.R. 61-85

